Transfer roller for transferring a formatted adhesive application

ABSTRACT

A transfer roller serves to transfer a formatted adhesive application from an adhesive roller of an adhesive applicator to a continuously conveyed web, preferably a paper web. To adapt the transfer roller quickly and simply to the different formats of glue applications, the peripheral surface of the transfer roller is provided with radially moveable tappets or stamps, which lie closely side by side and which can be moved between an inserted inactive position and an extended active position, in a specified grid.

[0001] The invention relates to a transfer roller for transferring a formatted adhesive application from an adhesive roller of an adhesive applicator to a continuously conveyed web, preferably a paper web.

[0002] This type of adhesive applicator is known from the DE 196 34 594 A1 and is explained briefly with reference to FIG. 4 of the drawings. The adhesive applicator comprises an adhesive chamber, which is mounted on the machine frame (not illustrated) and exhibits a perpendicular U-shaped housing 1, whose underside is sealed by means of a floor plate (not illustrated). The vertical edges of the housing 1 are provided with sealing strips 2, which are employed at the adhesive rollers 3, 4, which are mounted in the machine frame and driven so as to rotate in the direction of the arrows. The adhesive is transferred from the adhesive roller 4 to the format members, disposed in a manner that is not illustrated on the periphery of the transfer roller 5. These format members are made of elastomeric material, for example rubber, and are fastened, for example cemented, on the periphery of the transfer roller. Between the transfer roller 5 and a counterpressure roller 6 runs a paper web 7, which is provided by the transfer roller with formatted adhesive applications.

[0003] The configuration of the adhesive applicator, apparent from FIG. 4, is relatively complicated, since for each application of glue the matching format members must be kept on hand and fastened to the transfer roller 5.

[0004] Therefore, the object of the invention is to provide a transfer roller of the class described in the introductory part that can be adapted quickly and simply to different formats of glue applications.

[0005] The invention solves this problem in that the peripheral surface of the transfer roller is provided with radially moveable tappets or stamps, which lie closely side by side and which can be moved between an inserted inactive position and an extended active position, in a specified grid.

[0006] The inventive transfer roller can be adapted quickly and simply to different adhesive application formats in that the corresponding stamps are extended. Thus, it is no longer necessary to fasten special format members on the peripheral surface of the transfer roller, since it is only necessary to activate the stamps corresponding to the desired format.

[0007] To make it possible to extend and insert the stamps in an especially simple manner, a preferred embodiment provides that each stamp can be inserted and extended by means of a separately driven electromagnet.

[0008] If the stamps can be inserted and extended automatically, and in particular by means of electric or electromagnetic activation or by driving by means of a pressure medium, it is possible to activate the stamps, which bring about the formatted application, directly before running onto the adhesive roller so that the glue format to be produced can be modified while the machine is running. In this embodiment it is possible to use a transfer roller with a smaller diameter than would be necessary for the length of the formatted adhesive application. Then the respective transfer roller makes several revolutions, for example, for each glue format to be applied. If larger adhesive formats are to be transferred, it can be done with a small transfer roller, which is inexpensive to produce and exhibits a correspondingly smaller number of stamps.

[0009] Another embodiment of the invention provides that each stamp can be activated by means of a mechanical T[=toggle] flip-flop along the line of a ball point pen mechanism. According to this embodiment, it is then simple to adjust the desired format of the adhesive applications, since the corresponding stamps can be activated by applying pressure. To deactivate, it is only necessary to apply pressure once again. Mechanical T flip-flops of this kind have been described, for example, on pages 117 to 120 of the book by K. Roth “Designing with Construction Catalogs” (Springer Verlag, 1982).

[0010] To depress the individual stamps, provided with a ball point pen mechanism, there can exist a bracket, which runs over the transfer roller in the axial direction. Said jacket is provided with tappets, which are provided with drives and are arranged concentrically in a row and with which the individual stamps can be activated and deactivated.

[0011] Preferably the peripheral surface of the transfer roller that is provided with the stamps is enclosed by a jacket made of an elastomeric material, for example rubber. This jacket also prevents the adhesive from penetrating into the slits between the individual stamps and their drive mechanism, a state that would result in bonding there.

[0012] Embodiments of the invention shall be explained in detail below with reference to the drawings.

[0013]FIG. 1 is a perspective view of a transfer roller with two cut stamps in an active and inactive state.

[0014]FIG. 2 is a sectional view of a transfer roller, whose radially moveable stamps can be activated by means of electromagnets, and

[0015]FIG. 3 is a sectional view of a transfer roller, whose stamps, provided with ball point pen mechanisms, can be activated and deactivated by means of tappets, provided with drives and arranged in a row.

[0016] The transfer roller 10, apparent from FIG. 1, exhibits a jacket, which comprises radially moveable stamps, which are arranged closely side by side on peripheral strips and axial lines and which exhibit square faces. The individual stamps can be slid by way of sleeve-shaped guide members 11 on radial pins 12, which are connected permanently together to a deeper lying intermediate jacket of the transfer roller 10. Between the floors of the sleeve-shaped members 11 and the pins 12, serving the guidance, are clamped compression springs 13, which endeavor to slide the stamps into the extended active position. On the sleeve-shaped members 11 are mounted flaps 14 with approximately square faces 15, which are bent in accordance with the diameter of the transfer roller 10. The faces 15 form in the inserted inactive state of the stamps a gridded peripheral surface of the transfer roller, which is depicted as a schematic drawing in FIG. 1.

[0017] The stamps can be moved into and out of position as well as be stopped in their inserted and extended positions by any arbitrary means.

[0018] According to the embodiment in FIG. 2, the stamps 11, 14 can be moved in and out of position electromagnetically. For this purpose the transfer roller is provided with a line or bus system 16, which is disposed inside the transfer roller 10. The radial pins 12, designed as electromagnets, are driven by this bus system over separate lines 17, whereby the current-driven electromagnets pull the stamps 11, 14 radially in the inward direction under compression of the springs 13 so that the stamps are located in their inactive state. If the electromagnets are without current, the stamps 11, 14 move into their active position, as apparent from FIG. 2. The active and inactive positions of the stamps are ensured by means of stops (not illustrated).

[0019] The bus system 16 is fed by a central supply and control unit 18 with the requisite energy to activate the electromagnets and with the electric pulses to drive the individual electromagnets. The bus system 16 assumes the sending and distribution of the control signals to the individual stamps. The adhesive pattern to be applied results from the position or activation of the individual stamps. Said position is specified by the central control unit 18. In the embodiment, according to FIG. 3, the individual stamps are provided with a T flip-flop in the form of a ball point pen mechanism 21. Thus, it is possible to activate the individual stamps 20 by means of a first depression and to deactivate by a second depression. To activate and deactivate the stamps 20 in a simple manner, the machine frame exhibits a holding bracket 22, where the cylinders 23 are arranged in an axial row. In said cylinders tappet-forming pistons 24 can be moved in and out. The cylinders 23 are assigned in the same number to the stamps 20, which are arranged in an axial row, so that by activating the tappets 24 the individual stamps 20 can be pressed down and thus activated and deactivated. The cylinders 23 can be activated, for example, pneumatically. Instead of pneumatically activated cylinders 23, the tappets 24 can also be activated electromagnetically.

[0020] The stamps 14, 15 and 20 of the transfer roller are enclosed by a tubular member 26, which is made of rubber or another elastomeric material and which rests sealingly against the end regions of the transfer roller that are not provided with stamps.

[0021] If individual stamps are activated, the rubber elastic cover 26 rests against the stamps in accordance with the peripheral contour of the stamps insofar as said stamps are moved out of the envelope of the cylinder, which corresponds to the inactive state of the stamps.

[0022] In operation only the activated stamps make contact with the glue roller and only the activated regions assume from the glue roller the adhesive application for transfer to the web to be covered with glue. 

1. Transfer roller (10) for transferring a formatted adhesive application from an adhesive roller of an adhesive applicator to a continuously conveyed web, preferably a paper web, characterized in that the peripheral surface of the transfer roller is provided with radially moveable tappets or stamps (11, 14, 20), which lie closely side by side and which can be moved between an inserted inactive position and an extended active position, in a specified grid.
 2. Transfer roller, as claimed in claim 1 , characterized in that each stamp (11, 14) can be moved into and out of position by means of a separately driven electromagnet.
 3. Transfer roller, as claimed in claim 1 or 2 , characterized in that the stamps (11, 14) can be activated directly before running up on the adhesive roller.
 4. Transfer roller, as claimed in claim 1 , characterized in that each stamp (20) can be activated by means of a mechanical T flip-flop along the line of a ball point pen mechanism.
 5. Transfer roller, as claimed in any one of the claims 1 to 4 , characterized in that the peripheral surface of the transfer roller that is formed by the faces of the stamps is enclosed by a jacket made of an elastic material. 